This invention relates to brick-molding apparatus, and more particularly to such apparatus which is operable to produce a brick with a roughened face.
For aesthetic and other reasons, it often is desired to produce bricks, or blocks, having irregularly roughened surfaces. To manufacture roughened bricks, or blocks, of concrete, it has generally been necessary in the past to form a block which is a whole number multiple of the size required and then break it along a plane extending normal to one of its sides to provide multiple blocks having irregularly roughened sides. In such previous methods those sides which previously had been joined along opposite sides of the cleavage line become the roughened surfaces of the blocks.
Others have attempted to roughen the surfaces of blocks by providing projecting teeth which extend at substantially less than a 90.degree. angle to the path of movement of a side of the brick, which projections were to form grooves in a surface of the block. These previous devices have proved unsatisfactory in that, for the most part, very regular lines are formed in the surface of the brick, rather than the desired irregularly roughened surface.
A general object of the present invention is to provide novel apparatus operable to form bricks, or blocks, having an irregularly, roughened surface along at least one of its sides.
More specifically, an object of the present invention is to provide novel apparatus which is operable to produce an irregularly roughened surface on a brick by providing a scraping, or tearing, of the surface of one side of the brick by a rigid member extending substantially normal to such face of the block as the member and block are moved relative to each other.
Still more specifically, an object is to provide a novel mold for a brick having interconnected side plates bounding a block-forming cavity for receiving block material. One of the side plates has a lip projecting outwardly from one of its edges substantially normal to the side. The mold is so constructed that a formed, uncured brick is discharged from the mold past said lip whereby the lip produces a tearing, or scraping, action along the face of brick adjacent thereto to produce a desired irregularly roughened effect.
Yet another object is to provide such novel apparatus which includes a bottom plate which is shiftable vertically relative to the side plates of the mold between a raised position adjacent the undersides of the side plates for forming a bottom of the mold and a position lowered a distance therebelow. Also included in such apparatus is a powered pusher above the mold operable to push down against the top of a brick formed in the mold for forcing it out through the bottom of the mold when the bottom plate is lowered. The bottom plate and pusher are mounted for movement vertically at substantially the same speed so that the bottom plate may continue to provide underlying support for an uncured brick as it is forced out of the bottom of the mold by operation of the pusher. This permits the brick to be forced past the projecting lip on a side plate to provide the required force for scraping, or tearing, the surface for roughening.